Continuously loaded submarine signaling cable



Feb. 13, w 5 SMITH r A CONTINUOUSLY LOADED SUBMARINE SIGNALING CABLE Filed March 28. I931 WsSmizk 15 J Gigrneit he JJV can,

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ITE YATES PATENT CONTINUOUSLY LOADED SUBMARINE SIGNALING CABLE Willoughby Statham Smith, Benchams, Newton Poppleford, Henry Joseph Garnett, Sevenoaks, and John Norman Dean, Orpington, England Application March 28, 1931, Serial No. 526,114, and in Great Britain April 11, 1930 7 Claims. (Cl. 17845) In the copending application of Smith, Garnett substance or a similar body or a homologue in and Channon, Serial No. 303,970, filed September the gutta percha. 4, 1928, now Patent No. 1,819,720, granted Aug. Moreover, when the interposed layer consists 18, 1931, there is described a loaded signaling of the gutta percha petroleum jelly mixture, the g cable in which the loading material before the electrical properties of this layer are intermediate to application of the insulating is surrounded with between those of the petroleum jelly-pressure a cushion of petroleum jelly or like viscous parafqualizin m dium next the conductor and th fin hydrocarbon, thickened with the addition of Outer layers of the insulation. This grad a medium such as rubber, gutta percha, balata or he e i al properties is advantage in Causthe like. ing a smooth potential gradient over the whole 65 It has been found that, even at sea bottom temt n O th die ectr c. peratures, many organic dielectrics absorb over A d n to a ur er eatu e 0 the nvention long periods of time, appreciable quantities f a continuously loaded submarine cable having a the parafiin hydrocarbons used in the preparation pr s r q liz ng m d m surrounding the loadof the above mentioned pressure equalizing mematerial is provided t a p a i y of aye to diums. For example, rubber and certain rubber- 0f insulatifm, the Specific ihdllfiti'v'e p y of bitumen mixtures n when placed in Contact which layers decrease from the outer to the inner with petroleum jelly. Thus, when a continuously layer whereby a Smooth potential gradient is loaded si nalin conductor is surrounded with tainedg g The invention is illustrated in the accompany- 75 a layer of a pressure equalizing medium comprising petroleum jelly, and is then insulated with a mg drawll'lg In Which Flgures 1 and 2 are diarubber containing composition, the insulation f fi sectloml S of cores made will, owing to the presence of the rubber, gradig dancfwlth the mventwn' ually absorb the petroleum jelly from the presigfg C0D er conductor 80 sure equalizing medium, whereby the valuable 2 regregents 2 material pmpert1e of the latter are t t 3 represents petroleum jelly pressure equaliz- According' to the present 1nvent1on, in a conmg medium tinuously loaded submarine signaling cable havrpresenizs a protective layer of dirt and resin mg pressure .equalizing medium Surrounding the free gutta percha or of deresinated balata. 85 loadmg material and an Puter layer of 5 and 6 represent layers of a mixture of rubbertion for which 2 meqmm has an ammty or bitumen plus dirt and resin-free gutta percha. vice versa, there 18 provided a layer of lnsula- In Figure tion intermediate said medium and the outer 10 representsacopperconducton insulation, and which does not react with the 20 represents loading materiaL 96 latter- 30 represents petroleum jelly pressure equaliz- A continuously loaded submarine signaling m medium cable having a pressure equalizing medium comrepresents a layer f 5 t and resinprising a paraiiin hydrocarbon such as petroleum free gutta percha plus 40% petroleum 11 40 y, y 13% plovided With a layer of gutta 50 represents a layer of 80% dirt and resin- 95 percha and/or balata, which are materials not free utta percha plus 20% petroleum jelly.

a c d y the paraffin hydiocalbon, intelmecc represents a layer of dirt and resin-free diate said medium and the outer insulation which gutta perch? may be of rubber or rubber material. Preferably In th case r the gutta percha and/0r balata is tr a as to 40 represents a layer of deresinated balata 100 remove the whole or part of the resins and/0r 1us4o% petroleum jelly.

dirt. 50 represents a layer of deresinated balata Preferably, however, the intermediate layer plus 20% petroleum jelly.

consists of a mixture of dirt and resin free gutta 60 represents a layer of 50% rubber bitumen 50 p a and Petroleum J lly described in our mixture plus 50% dirt and resin-free gutta percha. 1' co-pendihg application 499,$6- It has found When an intermediate layer consisting of a that under the Working conditions of the cable, mixture of gutta percha with petroleum jelly is the ht tendency of gutta p to a sorb D employed, a mixture containing up to about 30% troleum jelly is reduced to insignificant proporof petroleum jelly will be found suitable. Mixtions by the presence of a certain amount of that tures containing 59% or even higher amounts may however, be employed since the mixtures when subjected to a heat treatment in the manner described in the copending application of Smith, Garnett, and Dean, Serial No. 413,398, filed December 11, 1929 are rendered sufiiciently stable although their use is limited by their softness.

In the accompanying claims the term gutta percha is to be read to include balata or the like.

What we claim is:

1. In a continuously loaded submarine signaling cable having a pressure equalizing medium surrounding the loading material, an outer layer of insulation for which the pressure equalizing medium has an affinity or vice versa, and an intermediate layer of insulation which does not react with the outer insulation disposed between and separating the pressure equalizing medium from the layer of insulation, said intermediate layer comprising a mixture of the material of the outer insulation and the material of the pressure equalizing medium.

2. In a continuously loaded submarine signaling cable the combination of a conductor, a layer of loading material continuously applied to said conductor, a pressure equalizing medium comprising a paraffin hydrocarbon surrounding the loading material, an outer layer of insulation comprising rubber having an affinity for parafiin hydrocarbon and an intermediate layer of gutta .percha separating said medium from the outer prising an intermediate layer of gutta percha from which the dirt and resin have been removed.

5. The combination claimed in claim 2 comprising an intermediate layer consisting of a mixture of dirt and resin free gutta percha with a semi-solid refined petroleum product.

6. In a continuously loaded submarine signaling cable the combination of a conductor, a layer of loading material applied continuously to the conductor, a pressure equalizing medium containing parafiin hydrocarbon surrounding the loading material, and insulation comprising layers of dirt and resin free gutta percha incorporated with a semi-solid refined petroleum product the content of which in each successive layer decreases progressively with the distance of the layer from the conductor.

7. In a continuously loaded submarine signaling cable, the combination of a conductor, a layer of loading material continuously applied to said conductor, a pressure equalizing medium comprising a parafiin hydrocarbon surrounding the loading material, an outer layer of insulation such as rubber having an affinity for paraffin hydrocarbon, and an intermediate layer of insulation which does not readily absorb the hydrocarbon disposed between and separating said medium from the outer layer of insulation, said intermediate layer comprising material whose dielectric properties are not appreciably inferior to those of the outer layer.

WILLOUGHBY STATHAM SMITH. HENRY JOSEPH GARNETT. JOHN NORNEAN DEAN. 

